I can vouch for their quality ,I bought mine from them about 4 years ago and have had no issues apart from the teeth on the handle which turn the cog to lower the jack have worn down just enough so that when the jack handle is at its lowest point it prevents the cogs from meshing thus not allowing the jack to be closed at its lowest point.
And everything I own is low
lifting the car just that little bit whilst sliding the jack under is the norm.
and when you have to close the hydraulics then lower the lever the jack raises just that half inch more - grrrr.
But yeah Ive lifted things that I thought would bust it and it just hangs in there . good stuff.